"Performances will determine who actually ends up being the eighth-inning guy." -- Brad Ausmus

LAKELAND, Fla. -- Joe Nathan will pitch the ninth. If all goes as planned, either Bruce Rondon or Joba Chamberlain will pitch the eighth.

Manager Brad Ausmus expects those two to compete for the job in spring training.

"Right now, Joba Chamberlain and Bruce Rondon are probably the two guys in my mind who you think about as eighth-inning guys for the team," Ausmus said Saturday afternoon. "Performances will determine who actually ends up being the eighth-inning guy. That being said, it could change once you move into the season. … Even if I know coming out of spring training who that is it doesn't mean it's going to stay that way."

Having someone lock up and succeed in the role as the setup man is integral to the success of the bullpen for the Tigers. Joe Nathan is an established, successful closer. But the rest of the pitchers in the bullpen have question marks.

Rondon could not put a stranglehold on the closer's job last spring and started the season in Triple-A Toledo. He pitched well -- even dynamically -- at times late in the season, but was sidelined by elbow trouble. Health and youth are two issues he will have to overcome.

Chamberlain has battled injuries and inconsistency in his career. He had a 2.83 ERA and a 1.047 WHIP in 27 games for the Yankees in 2011, but his ERA and WHIP have climbed since then. He has not had a WHIP below 1.500 in either of the past two seasons and had a 4.93 ERA and 1.738 WHIP in 2013 for the New York Yankees.

Al Alburquerque is unhittable when he's on top of his game, but has struggled finding the strike zone at times. Phil Coke struggled last season to the point that he was sent to Triple-A Toledo and has seen his WHIP climb in every season he's been in the majors. The Tigers think highly of Ian Krol, another left-hander, but he struggled against right-handed hitters in 2013 and might need a bit of time to develop into a consistent major-league pitcher.

The perfect scenario for Ausmus and the Tigers obviously would be for both Chamberlain and Rondon to pitch well this spring.

"I hope one of them grabs it," Ausmus said. "Now, if they both grab it, then there's a decision to be made. If they both go out there and pitch equally well, it's a good thing, but then now I have to make a decision."

Ausmus said the identity of the setup role could change throughout the season, but it likely will not change back and forth, say, in the course of one series.

"You could go matchups," he said, "but I prefer to kind of let the bullpen pitchers have an understanding where they are and when they are going to come into games so they can mentally and physically prepare over the course of a game."